| 摘要 |
A light emitting diode (LED) light source, LED driver circuitry and methods for controlling the brightness of an LED light source are presented, in some embodiments, an LED driver control circuit receives a dimming command signal to dim the LED light source, modulates a continuous direct current (DC) level to dim the LED light source, and determines that a predetermined threshold level has been reached. At this time, the process includes initiating a fixed pulse width generator (PWG) control signal having a fixed duty cycle, automatically adjusting the LED current amplitude to its nominal current level, and decreasing the current amplitude while the fixed PWG control signal is active to achieve commanded lower dimming of the LED light source. |
